1. Field of the Invention
This invention relates to a process for preparing supported, iron sulfide promoted molybdenum and tungsten sulfide catalysts, the supported catalyst species prepared by such process, and to the use of such supported species for hydroprocessing processes, particularly hydrotreating. More particularly, this invention relates to the preparation and use of catalysts useful for hydroprocessing processes, such as hydrotreating, wherein said catalysts are formed by heating, at elevated temperature, in the presence of sulfur and under oxygen-free conditions, a composite of support material and one or more catalyst precursor salts containing a thiometallate anion of Mo, W or mixture thereof and a cation comprising one or more divalent promoter metals at least one of which is iron, wherein said promoter metal or metals are chelated by at least one neutral, nitrogen-containing polydentate ligand, and wherein said additional divalent promoter metal, if any, is selected from the group consisting of Ni, Co, Mn, Zn, Cu and mixture thereof.